Just five days before the legislature is to reconvene in special session to adopt a new map setting out the boundaries of the state's eight congressional districts for the next decade, House leaders backed one plan and Senate leaders said they intended to consider several others. No one could predict exactly how the differences would ultimately be resolved, nor how long that might take.

"We're back to where we were two months ago," said Sen. John A. Pica Jr., D-Baltimore, chairman of a special Senate committee on redistricting.

The process of adopting a new plan was turned topsy-turvy Thursday night when the Governor's Redistricting Advisory Committee scrapped the map it had backed since Aug. 20 and unexpectedly replaced it with one that, among other changes, would put Representative Helen Delich Bentley, R-Md.-2nd, in the same, mostly Anne Arundel County district with Representative Tom McMillen, D-Md.-4th.

Until then, the committee and one of its key members, Senate President Thomas V. Mike Miller Jr., D-Prince George's, had pushed a plan that would have put Mrs. Bentley in an Eastern Shore district with fellow Republican Wayne T. Gilchrest, R-Md.-1st.

Mr. Miller had backed the argument from Mr. McMillen and others that Democrats should try to protect each other at the expense of Maryland's minority party -- the Republicans.

But Gov. William Donald Schaefer was eager to see Mrs. Bentley preserved in her beloved Baltimore port area, viewing her strong rTC maritime voice in Congress as important to the state. The other members of the delegation obviously agreed, with five of the eight members pushing one plan that would place Mr. McMillen in a district with Mr. Gilchrest.

With Mr. Miller vacationing in Ireland, the remainder of the committee voted 3-1 for a revised plan that Speaker R. Clayton Mitchell Jr., D-Kent, said the House of Delegates could support, and which the governor characterized as "fairer all around" and as safe from his previously threatened veto.

Now the problem rests in the Senate, where it appeared possible that the committee's revised version might not even be introduced, much less approved.

"If Miller had [the required] 32 votes to pass that other plan, I guarantee you he has 17 [the minimum required] to stop this one," said Sen. Michael J. Wagner, D-Anne Arundel, one of the new plan's opponents.

Mr. Miller, still overseas, said through an aide that he would not comment until after he returned to Maryland later today.

The unanswered question yesterday was how Mr. Miller would react: whether, angered by the committee's vote, he will stubbornly align the Senate behind another plan and refuse to budge, or whether he will show some willingness to find a compromise solution.

Delegate Samuel I. "Sandy" Rosenberg, D-Baltimore, a House leader, warned that it would reflect poorly on the entire legislature if the session deteriorated "into bickering with each other and showdowns."

At least four other plans were expected to be introduced in the Senate, including two under Mr. Pica's name that would place either Mr. McMillen and Mr. Gilchrest, or Mrs. Bentley and Mr. Gilchrest, in the same district. The latter plan also would expand Mr. McMillen's district to include Worcester, Wicomico and Somerset counties, a split of the Eastern Shore surely to be opposed by House Speaker Mitchell.

Senate Majority Leader Clarence W. Blount, D-Baltimore, also was expected to introduce the plan that Mr. Miller personally favors, a slightly amended version of the original plan adopted by the advisory committee in August. That version would leave ** Mrs. Bentley in Mr. Gilchrest's Eastern Shore district but give her the port precincts around Dundalk and Essex. It also would restore Howard County precincts to the 3rd Congressional District represented by Democrat Benjamin L. Cardin that he would have lost in an earlier version.

Two Republicans, Minority Leader John A. Cade, R-Anne Arundel, in the Senate and John J. Bishop, R-Baltimore County, in the House also are expected to introduce plans that would create a majority-black district in the Washington suburbs but keep the incumbent congressmen in their present districts.

"Everybody likes my map," boasted Mr. Bishop, who said one of his goals was to prevent citizens from being moved from one district to another as much as possible.

However, he admitted that it had one serious political flaw: It would leave Representative Steny H. Hoyer, D-Md.-5th, who is ++ white, in the new majority-black district rather than moving the high-ranking House Democrat into a politically "safe" district, as Democratic mapmakers are striving to do by shifting his district into Southern Maryland.

The machinations left some legislators, such as freshman Sen. Christopher J. McCabe, R-Howard, watching helplessly from the sidelines as forces beyond their control chopped up their districts and dealt out the parts to two, three or even four %J different congressmen.

"I look at this whole process as the ultimate insiders' game," he said. "The [advisory] commission had public hearings, but invariably it is an insiders' game dominated by the leaders in Annapolis and the congressmen. The people have little or no say."